Interesting comparison…

Long day yesterday helping a friend, got back late, so no time to research anything…

But this is rather a interesting comparison of the Periodic table before and after Neils Bohr.

Bohr calculated the atomic weights of the various elements.

Comments

Interesting comparison… — 8 Comments

  1. I don’t think I’d ever seen it laid out by atomic weights before. That could be useful to a student. It really illustrates the progression well.

    • I liked the old text (195X) Pa left lying around. It pointedly did NOT start with the Periodic table, but did talk about how elements were similar. By the time the Table was introduced it was not ‘The Big Scary Complicated Thing’ at the front of the book, but “Whoa, this explains so much, it’s so… obvious and beautiful.”

      Perfect? No. Better than almost everything else? Oh, yeah.

  2. Here’s a more up to date list that can be sorted multiple ways – even Bohr didn’t think of all of them!
    https://www.lenntech.com/periodic/mass/atomic-mass.htm

    I noted that the most abundant isotope list was “according to Glenn T. Seaborg,” another highly influential nuclear chemist and Nobel Prize winner who created nine or ten new elements, including Pu while working on the Manhattan Project.

    I’ll bet both those gentlemen would recoil at the thought of “science” ever being “settled”!!

  3. Simple lists are neat, but I still prefer the one based around the electron shell and polarity of the atom’s most stable isotope.

    I know, weird, but as soon as the electron shell theory and the polarity theory were explained to me, I got it and it really made the modern periodic table so darned easy to understand.

    Though it is interesting to see just a list of from Hydrogen to whatever overly large abortion of an atom they’ve recently made. And to see where the gaps are in the atomic number.

  4. The textbooks I had in the 1960s and 1970s still had the “classic” Mendeleev tables, up through high school chemistry and physics.

    Some years ago I discovered there were other versions, some of them downright whimsical.

    And if you’re only familiar with Mercator projection world maps, search “types of world maps” and be prepared for some really strange maps…

  5. Cedar/Orvan- Simple for those who weren’t scientists! 😉

    Tom- Yep, pieces of history…

    Beans- Good point, and yes there are gaps!

    TRX- I learned on Mendeleev tables too! I was a navigator in the Navy, YES there are some ‘strange’ maps out there!!!

  6. I remember my HS chem teacher (a delightful nun, BTW) saying that when we encounter the remains of a long-gone alien civilization, the Rosetta Stone will be their periodic table. Assuming they had gotten that far, of course.